For those who did not see my comment in the gist, I'll paste it here: "Probably the performance threshold Google has for its consumer facing products - if it r

For those who did not see my comment in the gist, I'll paste it here: "Probably the performance threshold Google has for its consumer facing products - if it runs slow on Firefox, then it would have normally have been a release blocker." Google cares probably the most out of any tech company I have seen about performance, especially with any consumer facing apps. CSP would probably be trivial for Google to fix. Animations/transitions similarly so. The only real explanation that makes sense is performance.